Unfortunately you don't need meta knowledge for this game to be easy even on tactician, if you're an rpg veteran.
Depends on the cRPGs you played before. If you come from the MMORPG side, action RPGs or even Wizardry, tactician will feel hard because a lot of the little things that help with fights are just non-intutitive to these players. If you played P&P RPGs or D&D before this will make it easier, though even then your idea that tactician is too easy is really, wildy off the mark, for 95% of players tactician is too hard and most of those who tried it will go back to balanced.
This is the Codex tips and tricks thread. I expect people here to be of a little more refined caliber. As in, the context for my post was: if you know cRPG combat and rules. You don't even need 5E metaknowledge.
And the fact is, if you do, this game is very, very easy. For example, I just did the Steel Titan fight, and even though I had no clue about its mechanics and just took hits left and right, I didn't reload. That's my lasting impression of BG3's difficulty: that I run into fights, obviously handle them very poorly because I have no idea about their mechanics, yet I never need to reload. Another fight that was like this was:
which was the hardest fight in the game except the starting cambion for me! *And I didn't even know his sentries would die when he died, so I killed those (total of 1000+ hit points) first!*
Bear in mind this is without using the surface/push down ledges system at all. It's just numbers vs. numbers.
Two most important reasons are:
1. Too many sources of easy damage mitigation
2. Copy-pasted 5E's weak "healing word"-gameplay which makes it impossible to go down - you got even 1 man still standing, you might still be in the fight
I realize this game is impossible on normal for 80% of normies. That's not because they're bad, that's just because cRPG difficulty varies wildly with metaknowledge of the genre.
But, what you're really asking me is "very easy relative to what" since the most annoying thing in RPG discussion is someone saying "this RPG is easy" and it turns out they just think all RPGs are easy. Well, relative to: WotR on Unfair, UnderRail, Icewind Dales, BGs (they are easy games once you understand them, but still offer more reloads than BG3), GoldBox games, Wizardry 8 - most RPGs, really.
Solasta is a recent exception I can think of that's easier on the "insane" difficulty. Maybe Expeditions: Viking as well. But there are not many.